What's the best and simplest way to achieve WAN redundancy?

[Dan_17717]

Hi All,

I like to configure our 3560x so that it will fail over if the MPLS link is down.  I have tried adding the 2nd default route like so:

ip route 0.0.0.0 0.0.0.0 172.22.130.1

ip route 0.0.0.0 0.0.0.0 172.22.140.2 10

After disconnecting the MPLS connection, the 2nd default route did not take affect.  When I do a show ip route in the 3560x, the default route for the MPLS is still there.  Do I need to configure an IP SLA for this to work?  

Thanks,

Dan

[Nagendra Kumar Nainar]

Hi Dan,

What is the device that is configured with 172.22.130.1 address?. Is it the MPLS edge router?.

When you say, "After disconnecting the MPLS connection", did you mean the interface to MPLS router is down? (the one configured with 172.22.130.2). If so, the next entry should be installed in RIB once the primary interface is down. If the L2 connection is in a way that the interface will stay up, you need IP SLA.

You can use IP SLA to ping the MPLS router with source as 172.22.130.2. Now assign the SLA to track and assign the track to static route. Something like blow,

ip sla 1

<Config to send echo to address>

track 1 ip sla 1 state

ip route <prefix> <mask> <nexthop> track 1

-Nagendra

[Dan_17717]

The 172.22.130.1 is a router provided by our MPLS provider and managed by them.  Yes, I disconnected the interface configured with 172.22.130.2 to see if it will failover.  What do you mean by RIB?  How do I go about doing that?

Thanks

[Nagendra Kumar Nainar]

The 172.22.130.1 is a router provided by our MPLS provider and managed by them.  Yes, I disconnected the interface configured with 172.22.130.2 to see if it will failover.  

<Nagendra> When you disconnect the interface and if the protocol goes down, the address 172.22.130.0 will be removed from your local Routing table (or RIB) and should update the next static entry. 

What do you mean by RIB?  How do I go about doing that?

<Nagendra> RIB is routing table. 

Do you have the address configured on vlan interface or under any physical port?. Can you share the configuration from 3560?.

[Dan_17717]

I have vlans configure for the MPLS and the ISP2.  I thought that disconnecting the MPLS interface would remove the route, but it doesn't.  I have not tried the IP SLA config yet.  But would configuring with IP SLA remove the route if it's disconnected?

[Nagendra Kumar Nainar]

If you have the address configured on vlan interface, it will not go down when you disconnect the L2 circuit (if there are more L2 ports part of same vlan). So the static route will remain in your routing table.

You can try IP SLA.

-Nagendra

[Dan_17717]

Ok, I will try IP SLA when time permits.  Thanks Nagendra.